1 # Copyright 2016, Tresys Technology, LLC 2 # 3 # This file is part of SETools. 4 # 5 # SETools is free software: you can redistribute it and/or modify 6 # it under the terms of the GNU Lesser General Public License as 7 # published by the Free Software Foundation, either version 2.1 of 8 # the License, or (at your option) any later version. 9 # 10 # SETools is distributed in the hope that it will be useful, 11 # but WITHOUT ANY WARRANTY; without even the implied warranty of 12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 # GNU Lesser General Public License for more details. 14 # 15 # You should have received a copy of the GNU Lesser General Public 16 # License along with SETools. If not, see 17 # <http://www.gnu.org/licenses/>. 18 # 19 from collections import namedtuple 20 21 from .context import ContextWrapper 22 from .descriptors import DiffResultDescriptor 23 from .difference import Difference, Wrapper 24 25 26 modified_nodecon_record = namedtuple("modified_nodecon", ["rule", 27 "added_context", 28 "removed_context"]) 29 30 31 class NodeconsDifference(Difference): 32 33 """Determine the difference in nodecons between two policies.""" 34 35 added_nodecons = DiffResultDescriptor("diff_nodecons") 36 removed_nodecons = DiffResultDescriptor("diff_nodecons") 37 modified_nodecons = DiffResultDescriptor("diff_nodecons") 38 39 def diff_nodecons(self): 40 """Generate the difference in nodecons between the policies.""" 41 42 self.log.info("Generating nodecon differences from {0.left_policy} to {0.right_policy}". 43 format(self)) 44 45 self.added_nodecons, self.removed_nodecons, matched_nodecons = self._set_diff( 46 (NodeconWrapper(n) for n in self.left_policy.nodecons()), 47 (NodeconWrapper(n) for n in self.right_policy.nodecons())) 48 49 self.modified_nodecons = [] 50 51 for left_nodecon, right_nodecon in matched_nodecons: 52 # Criteria for modified nodecons 53 # 1. change to context 54 if ContextWrapper(left_nodecon.context) != ContextWrapper(right_nodecon.context): 55 self.modified_nodecons.append(modified_nodecon_record(left_nodecon, 56 right_nodecon.context, 57 left_nodecon.context)) 58 59 # 60 # Internal functions 61 # 62 def _reset_diff(self): 63 """Reset diff results on policy changes.""" 64 self.log.debug("Resetting nodecon differences") 65 self.added_nodecons = None 66 self.removed_nodecons = None 67 self.modified_nodecons = None 68 69 70 class NodeconWrapper(Wrapper): 71 72 """Wrap nodecon statements for diff purposes.""" 73 74 def __init__(self, ocon): 75 self.origin = ocon 76 self.ip_version = ocon.ip_version 77 self.address = ocon.address 78 self.netmask = ocon.netmask 79 self.key = hash(ocon) 80 81 def __hash__(self): 82 return self.key 83 84 def __lt__(self, other): 85 return self.origin < other.origin 86 87 def __eq__(self, other): 88 return self.ip_version == other.ip_version and \ 89 self.address == other.address and \ 90 self.netmask == other.netmask 91
